1. Field of the Invention
The present invention relates to a mobile terminal of a communication system and, in particular, to an external connection interface emulation method and apparatus for a mobile terminal for exploiting the mobile terminal as a network adaptor of another terminal.
2. Description of the Related Art
Technological advancements and rising usage of mobile communication have dramatically influenced people's everyday life. As a result of these technological advancements, mobile communication devices are becoming ever more popular and widely accepted for data communications as well as for conventional voice communications.
Wireless Broadband (WiBro) is a wireless broadband Internet technology developed for satisfying mobile user's demands for wireless voice and data communication. WiBro provides the user with voice and data connectivity anytime and anywhere even on the move.
WiBro operates in the 2.3 GHz band and covers about 1 Km range. WiBro supports high-speed data service indoor, outdoor stationary, pedestrian-speed, and below-60 Km/h mobile environments. WiBro also provides high speed and reliable Internet service at low cost relative to other communication networks.
Recently, various handheld devices such as Personal Digital Assistants (PDAs) and Smart phones are equipped with a Wireless Local Area Network (WLAN) or WiBro module. Code Division Multiple Access (CDMA) and Global System for Mobile communication (GSM) phones equipped with the WiBro module have emerged.
In order to access the Internet using WiBro service, the user needs a WiBro-enabled device, or the user could purchase a WiBro communication modem if the user already has a portable terminal, which does not support WiBro.
If the user has a WiBro-enabled handheld terminal and wants to access the Internet using another terminal that does not support WiBro, then additional cost may be incurred for accessing the Internet using the WiBro service.
Regarding CDMA, in order to access a CDMA network using a terminal such as a laptop computer that does not support CDMA communication, a USB modem emulation technique for connecting a CDMA phone to the laptop computer through a universal serial bus (USB) cable has been proposed.
FIG. 1 is a block diagram illustrating a configuration of a conventional USB connection between two terminals. In FIG. 1, a laptop computer 110 and a CDMA phone 120 having respective USB ports 111 and 121 are connected with each other. CDMA phone 120 includes a CDMA modem 123 for processing incoming and outgoing signals through a CDMA network and a USB client module 125. The client module 125 couples USB port 121 with CDMA modem 123. USB client module 125 and USB port 121 are matched through the USB interface.
However, a conventional WiBro modem does not support the USB connection, making a USB connection-based WiBro service impossible, since pins of the USB client module cannot be directly connected to a WiBro modem. Particularly, some WiBro services requiring an authentication process using an identification card such as a Universal Subscriber Identification Module (USIM) may not be served using a direct USB connection.